1. Field of the Invention
This invention relates to golf clubs and more particularly to arrangements within that golf club to minimize the twisting and the torque effect upon the hitting of a golf ball.
2. Prior Art
Golf club design is directed towards two goals. The first goal is to maximize impact energy to the golf ball, so that the struck ball flies as far as possible. The second goal is for that golf ball, when hit, to fly as straight and true as possible. The prior art has attempted to reach these goals primarily by the design of the club head, the composition of the club head face, or the composition of the club shaft itself. Other prior art devices relate to swing training arrangements intended to physiologically program the golfer""s swing.
In order to increase the probability of impacting a force that causes a golf ball to fly straight, the face of the club must address the ball in a perfectly perpendicular attitude. Torque of the club must be taken into consideration. Torque is the rotation of the club shaft transferred to the club head-end face that causes the club face to impact the golf ball in a less than perpendicular manner. This torque is created by the mechanics unique to each golfer""s swing. Torque in the shaft, and an offset club face is what causes the ball to fly in less than a straight flight, as either in a hook or in a slice.
It is an object of the present invention to provide a golf club shaft that will minimize or eliminate any torque unique to each golfer.
It is a further object of the present invention to minimize or eliminate the characteristics of a golf club that would affect the ball going in anything else than a straight ball trajectory.
It is a further object of the present invention to provide a golf club having a club head speed that would reach maximum acceleration at the point that the golf club face impacts the golf ball.
It is a further object of the present invention to provide a golf club shaft that will increase the shaft flexibility but reduce or eliminate golf club shaft rotational torque.
The present invention utilizes a material for the golf club shaft to improve golf club shaft head speed and to minimize golf club shaft rotational torque. Such material is Nitinol (NiTi) that is a unique shape memory alloy of nickel and titanium. Nitinol is a material which will re-attain its original shape once its constraining forces are removed. Nitinol is one component of the present invention that imparts flexibility to the golf club shaft. The Nitinol material is responsible for both the flexibility of the shaft and the torque retardation of that golf club shaft.
The present invention utilizes one or more ribbons of Nitinol which may, when arranged according to the principles of the present invention, flex only in the direction of the large flat front and any parallel back face of the golf club head. A Nitinol ribbon cannot flex from side to side because of the I-beam principles unique to a flat ribbon design.
In the present invention, one or more elongated ribbons of super elastic material, for example preferably Nitinol or another metal or a superelastic plastic, are arranged along side one another. The Nitinol ribbons have an upper end and a lowermost end. The length of the longest ribbons may extend from about 44 to 54 inches and the ribbons may have a thickness of preferably about 0.001 to about 0.1 inches. In a preferred embodiment, the ribbons of Nitinol have a central long ribbon being sandwiched by a first pair of slightly shorter Nitinol ribbons, those three ribbons being sandwiched by a yet slightly shorter third pair of Nitinol ribbons, each set of pairs of Nitinol ribbons having a common upper end and each pair of Nitinol ribbons having lowermost ends spaced apart from the other lowermost ends of the other pairs of ribbons.
A preferred embodiment of the present invention comprises the multiple pairs of varying lengths of Nitinol ribbons sandwiched together and held together by a plurality of spaced apart restraining bands. The sandwich of multi-length Nitinol bands in a preferred embodiment are arranged within the hollow tubular shaft of the golf club, the upper end of the Nitinol band sandwich being disposed within the upper end of the handle portion of the golf club shaft. The lower end of the Nitinol band sandwich comprising the stepped down or reduced thickness of the Nitinol sandwich, residing in the lower end of the golf club shaft. The golf club shaft having at its lower end a golf club head. The golf club head has a generally planar face which is utilized to strike and impact the golf ball at the lowermost arcuate portion of the golfer""s swing.
The band of Nitinol ribbons sandwiched together are held securely within the hollow tapered shaft of the golf club by internal support means therewithin. Such internal support means may comprise a plurality of opposed spaced apart shelves or ledges within the club shaft. Those ledges or shelves would have progressively narrower gaps therebetween, proceeding towards the lower end of the shaft.
The bands of Nitinol are wider than they are thick. The wide portions of each Nitinol band defines a planar face thereof. The golf club head has a planar face thereon. The planar face of the Nitinol bands, in the present invention are preferably arranged parallel to the planar face of the golf club head, or to a horizontal dividing the sweet spot of the face. This planar arrangement with the stepped configuration of the Nitinol ribbon pairs sandwiching one another permits a front-back flexion with in combination with the golf club head weight, to create a xe2x80x9cwhipxe2x80x9d action of the golf club head to allow more golf club head speed and greater ball flying distance upon impact thereof. The reverse-graduated pairs of Nitinol ribbon bands tightly engaging the shaft (or comprising the shaft) prevent the golf club shaft torqueing. The combination of increased flexibility at the lower or distal end of the golf club shaft and the reduced shaft/head torque would create increased golf ball flight distance and greater likelihood of a straight flight of that golf ball.
A further embodiment of the internal support arrangement of the Nitinol ribbons therewithin, may comprise a sleeve of flexible plastic material enveloping the ribbons and filing any space between the ribbons and the inner walls of the shaft, the sleeve may in a further embodiment may also comprise the external surface of the shaft.
A yet further preferred embodiment of the present invention is contemplated by an adjustable juncture between the lowermost end of the golf club shaft and a receptive fitting in the golf club head into which the lower end of the golf club shaft mates. By rotating the plane of the Nitinol ribbons with respect to the plane of the face at the golf club head prior to the golf club being swung, may provide for compensation to erratic swinging conditions by the golfer. Such improved flexure and torque elimination would thus result.
The invention thus comprises a torque reduction and swing improvement arrangement for a golf club comprising a hollow elongated golf club shaft with a longitudinal axis therewithin, and having a handle portion at an upper end thereof, and a golf club head at a lower end of the shaft. A torque reduction arrangement of at least one ribbon of flexible planar material is disposed longitudinally within the shaft, the ribbon extending from the upper end of the shaft into the lower end thereof. The least one ribbon is secured within the shaft by a securement arrangement within the shaft. The torque reduction arrangement may comprise a plurality of ribbons of material within the shaft. The at least one ribbon may be formed of superelastic material. The superelastic material may be comprised of Nitinol. The plurality of ribbons may comprise a central elongated ribbon sandwiched between at least one pair of shorter ribbons. The plurality of ribbons may have an upper end at a common location at an upper end in the handle portion of the shaft. The plurality of ribbons may be held together by a band arranged therearound. The torque reduction arrangement may be supported within the shaft of the club by an arrangement of shelves pinchably disposed therein. The securement arrangement of said club may comprise a sleeve of engaging material disposed therearound. The sleeve of engaging material may be comprised of a sleeve of plastic. The club head has a planar surface thereon for impacting a ball, and the ribbon of planar material defines a planar surface which is disposed parallel to the planar surface of the club head. The golf club head may be rotatable with respect to the longitudinal axis of the shaft of the club to affect a displacement of the plane of the at least one ribbon relative to the planar surface of the head. The head and the lower end of the shaft have a splined mating relationship permitting the adjustable rotation therebetween.